Helmet



FIG. 1 is a perspective view of a helmet, showing our new design;

FIG. 2 is a right-side elevation view of the helmet of FIG. 1;

FIG. 3 is a left-side elevation view of the helmet of FIG. 1;

FIG. 4 is a front elevation view of the helmet of FIG. 1;

FIG. 5 is a rear elevation view of the helmet of FIG. 1;

FIG. 6 is a top plan view of the helmet of FIG. 1; and,

FIG. 7 is a bottom plan view of the helmet of FIG. 1.

The environmental structure shown in broken lines forms no part of the claimed design. 

CLAIM The ornamental design for a helmet, as shown and described. 